Antistrophus laciniatus

Antistrophus rufus

Antistrophus minor

Liposthenes glechomae

Antistrophus silphii

Antistrophus pisum

Phanacis taraxaci

Antistrophus chrysothamni

Antistrophus bicolor

Aylax laciniatus (Gillette)

Antistrophus laciniatus
Aulax laciniatus

Gall. (Plate XIV, Fig. 6.) In clusters on the receptacles of the flowers of rosinweed (Silphium laciniatum). Individual galls are egg-shaped and from 4 to 5 mm. in length.

Habitat. Illinois (Champaign).

According to Mr. C. A. Hart the galls occur in well-ripened, healthy looking flower heads, but do not show until the weather has removed the uninfested flowerlets. They are always produced in the sterile flowers of the disk, toward the center.


Aylax rufus (Gillette)

Aulax rufus
Antistrophus rufus

Gall. (Plate XIV, Fig. 7.) In the stems of rosin weeds (Silphium laciniatum, Silphium perfoliatum, Silphium integrifolium and Silphium terebinthinaceum).
There is not the slightest indication of a swelling upon the outer part of the stem and the larvae live in small oval cells in the pith of the plants.

Habitat. Illinois.

Aylax gillettei

Antistrophus minor
Aulax gillettei

Gall. Same as in A. rufus. [Desc for A rufus: In the stems of rosin weeds (Silphium laciniatum, Silphium perfoliatum, Silphium integrifolium and Silphium terebinthinaceum). There is not the slightest indication of a swelling upon the outer part of the stem and the larvae live in small oval cells in the pith of the plants.]

This species was bred by Prof. C. P. Gillette from the same stems of Silphium containing A. rufus. Two types of minor are before me and I regard this species to be nothing more than small specimens of A. rufus with ill-defined parapsidal and median grooves. The types are in the Illinois State Laboratory of Natural History. The name A. minor is preoccupied by a European species.


Aylax glechomae (Linne).

Cynips glechomae
Diplolepis glechomae
Aulax glechomae
Diastrophus glechomae
Aulax glechomatis
Liposthenes glechomae
Liposthenes glechomatis
Diastrophis similis
Aulax similis

Gall. (Plate XIV, Figs. 1, 2, 3.) On the petioles, leaves and sometimes on the stems of ground ivy (Glechoma hederacea). Monothalamous when simple, polythalamous when compound. The simple galls are round, green, and covered with short hairs. When compound they are very irregular in form and size and have two or more larval cells, which are held in position by coarse fibres. When dry and old the galls are brown, with a thin paper-like outer covering, which sometimes disappears when lying on the ground through the winter and the bleached fibres surrounding the larval cells look like little burrs. Diameter, 6-25 mm. 

Habitat. Europe; Massachusetts; New York; New Jersey; Connecticut; Ohio; Illinois.

Aylax leavenworthi (Bassett)

Antistrophus leavenworthi BASSETT
Aulax leavenworthi KIEFFER
Antistrophus silphii GILLETTE
Aulax silphii

Gall. (Plate XIV, Figs. 4, 5.) On the tips of the stems of rosin-weeds (Silphium integrifolium and Silphium perfoliatum). Polythalamous. Abrupt, subglobular, tumor-like swellings, usually stunted with aborted growths of leaves and stems. Green when fresh, dark brown and woody when dry. Internally (fig. 5) it is composed of white pith in which are many larval cells. Length, 30-75 mm. 

Habitat. Illinois (Champaign and Normal); Virginia (Petersburg); Mts. of Georgia (Macon Co.). 

The types of A. leavenworthi and A. silphii are before me and I cannot find any differences between the two. The gall on Plate XIV was made from one of Prof. Gillette's types of A. silphii. The type of A. leavenworthi is in the collection of the American Entomological Society and the gall is in poor condition. 

Aylax pisum (Walsh).

Antistrophus pisum WALSH
Aulax pisum KIEFFER
Asclepiadiphila stephanotidis ASHMEAD
Aulax stephanotidis KIEFFER

Gall. (Plate XIV, Fig. 10.) On the stems of Lygodesma juncea. Monothalamous. Round or oval, pea-like, containing a central cavity. It is soft, pithy and internally consists of a dense whitish spongy substance which ultimately becomes quite hard and compact. Diameter, 5-12 mm. 

Habitat. Nebraska; Missouri; South Dakota; Oregon. I have examined the types of the flies and galls of Asclepiadiphila stephanotidis in the United States National Museum, and I cannot find any differences between these and those of Antistrophus pisum, neither specifically nor genericallv. The galls of stephanotidis are from Oregon and Missouri and are said to be found on a species of Stephanotis.

Aylax taraxaci (Ashmead)

Gillettea taraxaci Ashmead
Aulax taraxaci

Gall. (Plate XIV, Fig. 8.) Along and surrounding the petiole or midrib of the leaf of the common dandelion (Taraxacum taraxacum). Polythalamous. Pithy, irregular, oblong swellings, usually composed of knottv swellings and occurring together and forming, oblong irregular galls. Length 25-50 mm. 

Habitat. Minnesota (Winona); New York; Canada (Ontario).

Aylax chrysothamni Beutenmuller

Aulax chrysothamni

Gall. (Plate XIV, Fig. 9.) On the stems, usually at the tips, of a species of Chrysothamnus (Biqelovia). Polythalamous. White and densely covered with a white felt-like pubescence. Elongate, rounded or club-shaped, enlargements of the twigs. White and pithy inside with many scattered larval cells. Sometimes two or three galls are in a row on the same branch. Length, 15-30 mm. Diameter 12-20 mm. 

Habitat. Arizona (Tucson).

Aylax bicolor (Gillette)

Antistrophus bicolor Gillette
Aulax bicolor Kieffer

Habitat. Illinois (normal).

The type of this species was sent to me for examination by Mr. C. A. Hart. In general appearance and color it is like Aulacidea bicolor, but the parapsidal grooves are different, the radial area is open at the costa, and the cubitus almost reaches the first cross-vein. The gall is not known. 


The North American Species of Aylax and Their Galls